Parts washers are known that use alternating wash and rinse cycles to clean parts, such as automotive parts, that are supported for cleaning in a cabinet. The wash cycle utilizes a wash manifold with nozzles thereon which receives pressurized heated fluid from a reservoir in the cabinet and directs a spray of such fluid towards the parts. The wash cycle creates low pressure steam in the cabinet which is exhausted from the cabinet by a steam exhaust. After the wash cycle, the rinse cycle is started wherein a rinse manifold is utilized and receives water from a fresh water source and directs the water against the parts to be cleaned. Hence, a closed loop system is produced wherein the wash cycle lowers the level of cleaning fluid in the parts washer, while the rinse cycle adds fluid thereto.
It is known to provide a structure for detecting the level of cleaning fluid in the parts washer such that the fluid level cannot rise above a "set-point." Hence, the rinse cycle duration is limited by the amount of water removed in the form of steam from the parts washer during the wash cycle. In addition, known float structures do not provide any means for sensing when the fluid level in the parts washer is at a dangerously low condition such as when heated elements in the bottom region of the parts washer are no longer submerged in cleaning fluid. Likewise, dangerously high conditions also are not detected in known parts washers.